Working long hours was linked to as much as a 70% increased risk of masked hypertension and a 66% greater risk of sustained hypertension in a recent study of 3,500 white-collar employees in Quebec, Canada.
The study, led by Laval University’s Xavier Trudel, PhD, and published in Hypertension Dec. 19, analyzed both traditional high BP and masked hypertension, or hypertension that isn’t apparent during routine clinical visits but exists outside of healthcare settings. Masked hypertension is estimated to affect between 15% and 30% of U.S. adults, and both types of elevated blood pressure are known risk factors for CVD.
Trudel et al. studied 3,500 employees at three public institutions in Quebec and found that compared with colleagues who worked 35 or fewer hours each week, people who worked 41 hours or more were far more likely to have some type of hypertension. Those who logged 49 hours or more every week were 70% more likely to have masked hypertension and 66% more likely to have sustained hypertension; people who worked between 41 and 48 hours per week saw a 54% greater likelihood of having masked hypertension and a 42% greater likelihood of having sustained hypertension.
“The observed associations accounted for job strain, a work stressor defined as a combination of high work demands and low decision-making authority,” Trudel said in a statement. “Future research could examine whether family responsibilities—such as a worker’s number of children, household duties and childcare role—might interact with work circumstances to explain high blood pressure.”
To simulate in-clinic BP readings in the study, Trudel’s team dispatched trained assistants to offices to check each participant’s blood pressure three times in one morning. The rest of a person’s workday was spent wearing a BP monitoring device that took readings every 15 minutes, culminating in at least 20 additional measures each day. This process was repeated three times, at years one, three and five of the study.
Trudel et al. reported that around 19% of their study population had sustained hypertension—including employees who were already on BP meds—and 13% had masked hypertension. The team said the link between hours worked and hypertension was similar between the sexes.
“People should be aware that long work hours might affect their heart health, and if they’re working long hours, they should ask their doctors about checking their blood pressure over time with a wearable monitor,” Trudel said. “Masked hypertension can affect someone for a long period of time and is associated, in the long term, with an increased risk of developing cardiovascular disease.
“We have previously shown that over five years, about one in five people with masked hypertension never showed high blood pressure in a clinical setting, potentially delaying diagnosis and treatment.”